Prescribing for Children

General prescribing principles for children

Prescribing of any drug in children requires very careful consideration of age, weight, and pharmacologic aspects of the drug in question. Children are particularly susceptible to adverse drug reactions and dosing errors, and this is compounded by the lack of paediatric labelling details for many common prescription drugs. The pharmacokinetics and pharmacodynamics of a given drug is frequently very different in children, compared to adults, and may vary considerably depending on the child’s age and stage of development.

In general, drug dosing in children should be weight-based (mg/kg), though note that the recommended weight-based dose may vary according to age (for example, the half-life of many drugs is prolonged in young infants, compared to older children, resulting in lower recommended doses according to weight). Also, maximum dose limits must be taken into account and for most drugs the adult maximum dose should not be exceeded.

Paediatric dosing tables are included in these guidelines to help determine the optimal dose when antibiotics are required in children. However, these tables do not replace clinical acumen, and doses should be adjusted accordingly if the child’s weight or developmental stage is considered to be outside of the typical values. If in doubt, use the weight-based dosing included in the tables.

Key principles for management of infections in children

Clinical assessment, based on the child’s age, history, risk factors, and physical examination, is critical in determining the presence of infection, the likelihood of viral versus bacterial infection, and severity

The vast majority of infections in children are caused by viruses, and antibiotic therapy provides no benefit

For many childhood infections, even when bacteria are implicated, the potential for harm from antibiotic therapy greatly outweighs any potential benefit

Children are less likely to carry resistant bacteria, compared to adults. Thus, where antibiotic therapy is indicated, narrow-spectrum agents should be used as first-line therapy

A “watch and wait” approach (+/- a delayed or “only if” prescription) is appropriate for many childhood infections, particularly if clinical assessment indicates a likely viral infection or an infection for which antibiotic therapy is unlikely to be of immediate benefit

Where antibiotic therapy is indicated, using the optimal dose for the shortest possible duration maximises the potential for eradicating the infection while minimising the risk of antibiotic resistance and secondary infections

In general, the recommended duration of antibiotics in children is shorter than for similar conditions in adults

(®Dose is based on 7.5mg/kg per dose twice daily)Preparations available: Clarithromycin Granules for Oral Solution: 125mg/5mls and 250mg/5mls.Tablets: 250mg and 500mg. Prolonged release tablets not recommended in children.

The table shows the mean values for weight and height and gender by age; these values may be used to calculate doses in the absence of actual measurements. However, the child’s actual weight and height might vary considerably from the values in the table and it is important to see the child to ensure that the value chosen is appropriate. In most cases the child’s actual measurement should be obtained as soon as possible and the dose re-calculated.